1. Field of the Invention
This invention relates broadly to liquid dispensers. More particularly, this invention relates to liquid dispensers having spray/foam nozzles and a nozzle door.
2. State of the Art
Trigger dispensers are ubiquitous in most American homes. They are supplied on plastic bottles which are used to contain and dispense many different kinds of household liquids such as cleaning liquids, scenting liquids, garden liquids, etc. Traditionally, these sprayers have been provided with a rotatable nozzle which rotates among three positions: off, spray, and stream. More recently, it has been desirable to provide trigger dispensers with a foaming nozzle.
The basic method of creating a foam is to discharge the liquid as a spray toward an obstruction that is vented to the atmosphere. The spray hitting the obstruction mixes the liquid spray with the air of the atmosphere producing the foam that is discharged from the nozzle. One simple way of achieving this is to put a screen in front of a conventional spray nozzle.
Most conventional spray nozzles are either cylindrical, frustroconical, or cubic. On a cubic nozzle, it is known to form a door with a live hinge extending from one of the exposed edges of the nozzle. The door is moveable from an open position where the outlet of the nozzle is not covered to a closed position where the outlet is covered. These doors may be used to protect the nozzle from dirt when the sprayer is not in use, minimize leaking from the nozzle when not in use, or they may be arranged to carry a screen and thereby make a spray nozzle dispense foam. In any case, the doors must be provided with some kind of locking mechanism which will hold them in the selected two positions (opened and closed).
Most nozzle doors lock to the opened or closed position with a frictional engagement. To lock the nozzle door in the opened position, it is known to provide frictionally engaging shoulders on one of the sides of the nozzle. The shoulders are, by necessity of nozzle dimensions, not very deep and thus do not securely engage the door. It is also known to provide an extension on the door with an orthogonal tongue which engages a mating groove or slot in the sprayer housing. This arrangement requires alterations to the sprayer housing as well as the nozzle and is thus more expensive to implement.